Article
Geosciences, Multidisciplinary
Behnam Shafiei Bafti, Istvan Dunkl, Saeed Madanipour
Summary: The study applied the fluorite (U-Th)/He thermochronology technique to date fluorite mineralization and elucidate the exhumation history of the Mazandaran Fluorspar Mining District in Iran. Results showed multiple cooling events occurring at different periods (from Late Cretaceous to Oligocene-Miocene), possibly influenced by factors such as magmatic activity and crustal tectonics.
GEOLOGICAL MAGAZINE
(2021)
Article
Geography, Physical
Saeed Madanipour
Summary: By using detailed morphological analyses and thermal modeling, this study documents the transition from tectonic exhumation to river incision and erosional exhumation in the Talesh Mountains. The late Miocene-early Pliocene incision and rapid exhumation are related to a base-level fall caused by the isolation of the Caspian Sea. The effect of this base-level fall then migrated to the margin of the Iranian Plateau.
EARTH SURFACE PROCESSES AND LANDFORMS
(2023)
Article
Geosciences, Multidisciplinary
Yang Chu, Mark B. Allen, Bo Wan, Ling Chen, Wei Lin, Morteza Talebian, Lin Wu, Guangyao Xin, Zhentian Feng
Summary: The paper presents new geochronology and thermochronology data for the Talesh Mountains in northwest Iran to study the exhumation patterns during the Arabia-Eurasia collision. Results show a shared exhumation history between Talesh and Alborz, with regionally enhanced exhumation in the Late Miocene. The Late Miocene onset of deformation may relate to a re-organization of Arabia-Eurasia plate convergence.
EARTH-SCIENCE REVIEWS
(2021)
Article
Geology
Michael H. Darin, Paul J. Umhoefer
Summary: The timing of the initial Arabia-Eurasia collision has been debated for decades, but a new plate tectonic reconstruction that includes the entire Arabian microcontinent and surrounding regions provides new insights. The study suggests that the collision began around 42 million years ago in the eastern Bitlis suture zone and gradually propagated towards central Anatolia and the Zagros Mountains.
INTERNATIONAL GEOLOGY REVIEW
(2022)
Article
Geology
Badieh Shahsavari Alavijeh, Ali Kananian, Saeed Madanipour, Martin Danisik
Summary: The study focuses on the exhumation history of the Nodoushan plutonic complex in the Iranian Plateau, revealing two main exhumation phases in the early and middle Miocene related to the collision between the Arabian and Eurasian Plates. The 'soft' initial stages of collision occurred in the early Miocene when the Arabian passive margin reached the subduction zone, followed by the final 'hard' collision with the continental margin in the middle Miocene.
INTERNATIONAL GEOLOGY REVIEW
(2022)
Article
Geochemistry & Geophysics
C. L. Colleps, N. R. McKenzie, W. R. Guenthner, M. Sharma, T. M. Gibson, D. F. Stockli
Summary: The volcanic eruptions and subsequent weathering of the Deccan Traps in India are believed to have played a significant role in global climate change. Utilizing low-temperature apatite (U-Th)/He thermochronology, researchers have been able to determine the impact of volcanic activity on the Earth's surface environment and establish new constraints on the northern extent of the Deccan Traps.
EARTH AND PLANETARY SCIENCE LETTERS
(2021)
Article
Geosciences, Multidisciplinary
Madison P. Taylor, Alexis K. Ault, Margaret L. Odlum, Dennis L. Newell
Summary: The study documents the depths and mechanics of fault slip along the seismically active Hurricane fault in Utah, showing that changes in hematite and silica-rich host rock contribute to fault weakening and promote rupture propagation.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Geochemistry & Geophysics
A. C. Moser, A. K. Ault, M. A. Stearns, J. P. Evans, W. R. Guenthner
Summary: The study on zircon (U-Th)/He thermochronometry in the Mecca Hills, CA, reveals the exhumation timing and patterns of Orocopia Schist and North American basement, suggesting that both basement units were exposed simultaneously around 24 Ma. The data also indicate widespread late Oligocene-early Miocene extension in the southwestern Cordillera than previously thought.
Article
Geosciences, Multidisciplinary
R. M. Flowers, P. K. Zeitler, M. Danisik, P. W. Reiners, C. Gautheron, R. A. Ketcham, J. R. Metcalf, D. F. Stockli, E. Enkelmann, R. W. Brown
Summary: The field of (U-Th)/He geochronology and thermochronology has experienced significant growth over the past 25 years. However, there is currently a lack of universally agreed upon protocols for reporting data and uncertainties. This study aims to address these issues and provides recommendations to enhance the reliability and cross-laboratory comparison of (U-Th)/He data.
GEOLOGICAL SOCIETY OF AMERICA BULLETIN
(2022)
Article
Geochemistry & Geophysics
E. M. Armstrong, A. K. Ault, K. K. Bradbury, H. M. Savage, P. J. Polissar, S. N. Thomson
Summary: During an earthquake, the energy generated by fault friction is dissipated as heat. The rise in temperature after an earthquake is important for determining the magnitude of past earthquakes, but it is difficult to accurately measure. Researchers compared two temperature-sensitive geochemical methods and found that they provided consistent estimates of the temperature rise after an earthquake.
GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS
(2022)
Article
Chemistry, Physical
Thierry Stoecklin, Lisan David Cabrera-Gonzalez, Otoniel Denis-Alpizar, Dayan Paez-Hernandez
Summary: In this study, a close coupling approach was used to investigate the bending relaxation of H2O induced by collision with He, taking into account the bending-rotation coupling within the rigid-bender method and using a 4D potential energy surface. The results indicate that the bending-rotation coupling is highly efficient in increasing bending relaxation as the rotational excitation of H2O increases.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Geosciences, Multidisciplinary
Peiping Song, Lin Ding, Liyun Zhang, Fulong Cai, Qinghai Zhang, Zhenyu Li, Houqi Wang, Morteza Khalatbari Jafari, Morteza Talebian
Summary: Two well-dated paleomagnetic poles were discovered in the Urumieh-Dokhtar magmatic arc in Central Iran, indicating that Iran was situated around 3.7 to 3 degrees of latitude south of its present position between 40 to 23 million years ago. The paleomagnetic declination data suggests that the Central Iran block may have undergone an approximately 11.6-degree clockwise rotation since the Late Eocene. The integration of the new data with the retrodeformed margins of the Zagros collision zone and contemporaneous Arabia positions provides a better understanding of the age and configuration of the Arabia and Eurasia assembly process, supporting the Arabia-Eurasia collision as a significant driver of global cooling and regional geological changes.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geochemistry & Geophysics
Robert G. McDermott, Alexis K. Ault, Jonathan Saul Caine
Summary: Unraveling complex slip histories in the dextral eastern Denali fault zone (EDFZ) in southwest Yukon, Canada has revealed multiple generations of foliated, high-aspect ratio hematite plates and indicated episodes of hydrothermal alteration and fault reactivation at aseismic to subseismic slip rates. The hematite He dates overlap previously documented surface uplift and shifting dynamics of the Yakutat microplate, pinpointing fault networks and deformation processes that accommodate regional deformation in response to far-field plate boundary processes.
EARTH AND PLANETARY SCIENCE LETTERS
(2021)
Article
Geochemistry & Geophysics
Benjamin Gerard, Xavier Robert, Djordje Grujic, Cecile Gautheron, Laurence Audin, Matthias Bernet, Melanie Balvay
Summary: In this study, new zircon (U-Th)/He (ZHe) ages and zircon fission track (ZFT) ages were analyzed from an age-elevation profile in Machu Picchu, Peru. The ZFT data showed older ages compared to other thermochronological data, while the ZHe data interestingly showed ages similar to apatite (U-Th)/He (AHe). It was proposed that He retention in zircon is linked to the damage dose, with a closure temperature that varies with alpha-dose. The study suggests that the closure temperature of ZHe at low alpha-dose ranges from 6 x 10(15) to 4 x 10(16) alpha/g, and is lower than previously thought. These findings strengthen previous geological conclusions and highlight a cooling rate at Machu Picchu that is approximately twice as important as deduced from AHe and apatite fission track data alone.
Article
Geochemistry & Geophysics
Alice Recanati, Nistor Grozavu, Younes Bennani, Cecile Gautheron, Yves Missenard
Summary: This study investigates the impact of various parameters on apatite (U Th Sm)/He (AHe) thermochronological dates using advanced data mining techniques. By excluding the influence of other parameters on helium retention, it is concluded that the chemistry and crystal dimensions of apatite do not significantly affect helium retention or AHe date dispersion. The research suggests that machine learning has the potential to correct errors or detect anomalies in predicting AHe dates.
EARTH AND PLANETARY SCIENCE LETTERS
(2021)
Article
Geochemistry & Geophysics
Lorenz Michel-Wolf, Todd A. Ehlers, Rebecca Bendick
Summary: In the earthquake cycle, some deformation is unrecoverable, especially in the accumulation of deformation in the forearc high topography. By comparing data over long timescales, we have identified the contributions of elastic and inelastic deformation, providing further insights into the limitations of simple mechanical models.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Article
Geosciences, Multidisciplinary
R. M. Flowers, P. K. Zeitler, M. Danisik, P. W. Reiners, C. Gautheron, R. A. Ketcham, J. R. Metcalf, D. F. Stockli, E. Enkelmann, R. W. Brown
Summary: The field of (U-Th)/He geochronology and thermochronology has experienced significant growth over the past 25 years. However, there is currently a lack of universally agreed upon protocols for reporting data and uncertainties. This study aims to address these issues and provides recommendations to enhance the reliability and cross-laboratory comparison of (U-Th)/He data.
GEOLOGICAL SOCIETY OF AMERICA BULLETIN
(2022)
Article
Geochemistry & Geophysics
Scott Jess, Eva Enkelmann, William A. Matthews
Summary: The timing of surface uplift in the Appalachian Mountains has been a topic of controversy. This study aims to resolve the exhumation history of the region using detrital laser ablation apatite (U-Th-Sm)/He dating. Results show a majority of Cretaceous dates, indicating a lack of significant Cenozoic exhumation. These findings have implications for understanding surface uplift and landscape evolution.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Article
Geosciences, Multidisciplinary
Todd A. Ehlers, Deliang Chen, Erwin Appel, Tobias Bolch, Fahu Chen, Bernhard Diekmann, Michaela A. Dippold, Markus Giese, Georg Guggenberger, Hui -Wen Lai, Xin Li, Junguo Liu, Yongqin Liu, Yaoming Ma, Georg Miehe, Volker Mosbrugger, Andreas Mulch, Shilong Piao, Antje Schwalb, Lonnie G. Thompson, Zhongbo Su, Hang Sun, Tandong Yao, Xiaoxin Yang, Kun Yang, Liping Zhu
Summary: This study investigates the impacts of climate change on permafrost, hydrology, and ecosystems on the Tibetan Plateau. By compiling existing studies, the authors show the present-day trends in environmental change and discuss two possible future pathways for the plateau ecosystems. They emphasize the importance of human intervention measures in determining the future of the region.
EARTH-SCIENCE REVIEWS
(2022)
Article
Multidisciplinary Sciences
Alexander Koptev, Matthias Nettesheim, Sarah Falkowski, Todd A. Ehlers
Summary: This article presents a geomorphic model of the studied area in southern Alaska. The results show that the interaction between tectonic deformation and surface erosion processes controls the rock uplift patterns in the region.
SCIENTIFIC REPORTS
(2022)
Article
Geosciences, Multidisciplinary
Svetlana Botsyun, Todd A. Ehlers, Alexander Koptev, Madelaine Boehme, Katharina Methner, Camille Risi, Christian Stepanek, Sebastian G. Mutz, Martin Werner, Daniel Boateng, Andreas Mulch
Summary: The Middle Miocene in Europe experienced significant changes in climate, environment, and vegetation. However, detailed reconstructions of temperature and precipitation patterns during this period are lacking. In this study, a high-resolution isotope-enabled general circulation model was used to investigate these changes. The modeling results are consistent with available temperature data, but show lower precipitation rates compared to pre-industrial times for central Europe. The changes in precipitation are attributed to shifts in pressure patterns and associated changes in wind direction and humidity. Additionally, the study found that changes in precipitation isotopes were larger in high elevation regions, while topography played a smaller role.
PALEOCEANOGRAPHY AND PALEOCLIMATOLOGY
(2022)
Article
Geosciences, Multidisciplinary
S. J. Ring, S. G. Mutz, T. A. Ehlers
Summary: The long-term extent of the Earth system response to anthropogenic interference remains uncertain. However, the geologic record offers insights into this problem as Earth has previously cycled between warm and cold intervals during the Phanerozoic. We present an updated compilation of surface temperature proxies for several key time intervals to reconstruct global temperature changes during the Cenozoic. Our results suggest that the Earth system was less sensitive to greenhouse gas forcing for most of the Cenozoic and that sensitivity must have increased by at least a factor of 2 during the Plio-Pleistocene. Slow feedbacks will raise global surface temperatures by more than 3 degrees C in the coming millennia, even if anthropogenic forcing is stabilized at the present-day value (2 W/m2), and that their impact will diminish with further warming.
PALEOCEANOGRAPHY AND PALEOCLIMATOLOGY
(2022)
Article
Geochemistry & Geophysics
Nevena Andric-Tomasevic, Alexander Koptev, Giridas Maiti, Taras Gerya, Todd A. Ehlers
Summary: The study investigates the process of slab tearing in the context of non-collisional geodynamics by using a thermo-mechanical numerical approach. It finds that parameters such as subduction obliquity angle, age of oceanic slab, and partitioning of boundary velocities play a significant role in the occurrence of slab detachment. The results show similarities to observed features in many subduction zones.
EARTH AND PLANETARY SCIENCE LETTERS
(2023)
Article
Geochemistry & Geophysics
Victor Sacek, Sebastian G. Mutz, Tacio C. Bicudo, Renato P. de Almeida, Todd A. Ehlers
Summary: This study reveals that the formation of the Andes, climate evolution, and sea-level oscillations were the controlling factors for the transition from intermittent marine to lacustrine environments in the Amazon before the formation of the transcontinental river. It is also found that the evolving climate shortened the time interval between the end of marine influence and the onset of the transcontinental Amazon River.
EARTH AND PLANETARY SCIENCE LETTERS
(2023)
Editorial Material
Multidisciplinary Sciences
Todd A. Ehlers
Summary: Changes to the landscape over millions of years drive Earth system processes.
Article
Geochemistry & Geophysics
Paul R. Eizenhoefer, Christoph Glotzbach, Jonas Kley, Todd A. Ehlers
Summary: The formation of the eastern European Alps is a result of the intrusion of the Adria plate into the European plate. Recent tomography has shown detached slab fragments, indicating continuous southward subduction of the European lithosphere. Orogen-scale exhumation driven by rock displacement along active faults reflects subduction polarity within the framework of Coulomb wedge theory.
Review
Geography, Physical
Sierd Cloetingh, Pietro Sternai, Alexander Koptev, Todd A. Ehlers, Taras Gerya, Istvan Kovacs, Johannes Oerlemans, Fred Beekman, Yan Lavallee, Donald Dingwell, Eszter Bekesi, Kristof Porkolab, Magdala Tesauro, Alessio Lavecchia, Svetlana Botsyun, Veleda Muller, Francois Roure, Enrico Serpelloni, Liviu Matenco, Sebastien Castelltort, Donato Giovannelli, Alberto Vitale Brovarone, Nadia Malaspina, Giovanni Coletti, Pierre Valla, Jon Limberger
Summary: Understanding the interactions between surface and deep Earth processes is crucial for scientific research in various areas. The TOPO-EUROPE initiative serves as a platform for integrated surface and deep Earth sciences. This review discusses the quantitative understanding achieved through TOPO-EUROPE and the potential for future research.
GLOBAL AND PLANETARY CHANGE
(2023)
Article
Geography, Physical
Hemanti Sharma, Sebastian G. Mutz, Todd A. Ehlers
Summary: This study estimates global changes in frost cracking intensity (FCI) and finds that frost cracking is most prevalent in middle- to high-latitude regions and high-elevation lower-latitude areas. The simulations show that the most severe impact of climate change on frost cracking occurred during the pre-industrial to Last Glacial Maximum period, while the Pliocene period had higher FCI in Greenland and Canada due to reduced glaciation.
EARTH SURFACE DYNAMICS
(2022)
Article
Geography, Physical
Astrid Oetting, Emma C. Smith, Jan Erik Arndt, Boris Dorschel, Reinhard Drews, Todd A. Ehlers, Christoph Gaedicke, Coen Hofstede, Johann P. Klages, Gerhard Kuhn, Astrid Lambrecht, Andreas Laufer, Christoph Mayer, Ralf Tiedemann, Frank Wilhelms, Olaf Eisen
Summary: This study investigates the Ekstrom Ice Shelf in Western Dronning Maud Land, East Antarctica, and provides evidence of past ice-sheet flow, extent, and retreat. Geophysical surveys reveal an incised trough and mega-scale glacial lineations, suggesting the presence of grounded ice in the past. The study also shows rapid ice retreat in the center of the trough and gradual retreat at the margins. The findings are significant for understanding the past ice-sheet conditions in the region.
Article
Geography, Physical
Mirjam Schaller, Todd A. Ehlers
Summary: Weathering of bedrock to produce regolith is crucial for supporting life on Earth and global biogeochemical cycles. This study investigates soil production, chemical weathering, and physical erosion rates along the climate and ecological gradient of the Chilean Coastal Cordillera, revealing regional variations influenced by tectonics, climate, and biota.
EARTH SURFACE DYNAMICS
(2022)